1 /*
2 * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 package sun.jvm.hotspot.oops;
26
27 import java.io.*;
28 import java.util.*;
29 import sun.jvm.hotspot.utilities.*;
30 import sun.jvm.hotspot.debugger.*;
31 import sun.jvm.hotspot.runtime.*;
32 import sun.jvm.hotspot.types.*;
33 import sun.jvm.hotspot.memory.CompactingPermGenGen;
34
35 // Oop represents the superclass for all types of
36 // objects in the HotSpot object heap.
37
38 public class Oop {
39 static {
40 VM.registerVMInitializedObserver(new Observer() {
41 public void update(Observable o, Object data) {
42 initialize(VM.getVM().getTypeDataBase());
43 }
44 });
45 }
46
47 private static synchronized void initialize(TypeDataBase db) throws WrongTypeException {
48 Type type = db.lookupType("oopDesc");
49 mark = new CIntField(type.getCIntegerField("_mark"), 0);
50 klass = new OopField(type.getOopField("_metadata._klass"), 0);
51 compressedKlass = new NarrowOopField(type.getOopField("_metadata._compressed_klass"), 0);
52 headerSize = type.getSize();
53 }
54
55 private OopHandle handle;
56 private ObjectHeap heap;
57
58 Oop(OopHandle handle, ObjectHeap heap) {
59 this.handle = handle;
60 this.heap = heap;
61 }
62
63 ObjectHeap getHeap() { return heap; }
64
65 /** Should not be used or needed by most clients outside this
66 package; is needed, however, by {@link
67 sun.jvm.hotspot.utilities.MarkBits}. */
68 public OopHandle getHandle() { return handle; }
69
70 private static long headerSize;
71 public static long getHeaderSize() { return headerSize; } // Header size in bytes.
72
73 private static CIntField mark;
74 private static OopField klass;
75 private static NarrowOopField compressedKlass;
76
77 public boolean isShared() {
78 return CompactingPermGenGen.isShared(handle);
79 }
80
81 public boolean isSharedReadOnly() {
82 return CompactingPermGenGen.isSharedReadOnly(handle);
83 }
84
85 public boolean isSharedReadWrite() {
86 return CompactingPermGenGen.isSharedReadWrite(handle);
87 }
88
89 // Accessors for declared fields
90 public Mark getMark() { return new Mark(getHandle()); }
91 public Klass getKlass() {
92 if (VM.getVM().isCompressedOopsEnabled()) {
93 return (Klass) compressedKlass.getValue(this);
94 } else {
95 return (Klass) klass.getValue(this);
96 }
97 }
98
99 public boolean isA(Klass k) {
100 return getKlass().isSubtypeOf(k);
101 }
102
103 // Returns the byte size of this object
104 public long getObjectSize() {
105 Klass k = getKlass();
106 // All other types should be overriding getObjectSize directly
107 return ((InstanceKlass)k).getObjectSize(this);
108 }
109
110 // Type test operations
111 public boolean isInstance() { return false; }
112 public boolean isInstanceRef() { return false; }
113 public boolean isArray() { return false; }
114 public boolean isObjArray() { return false; }
115 public boolean isTypeArray() { return false; }
116 public boolean isSymbol() { return false; }
117 public boolean isKlass() { return false; }
118 public boolean isThread() { return false; }
119 public boolean isMethod() { return false; }
120 public boolean isMethodData() { return false; }
121 public boolean isConstantPool() { return false; }
122 public boolean isConstantPoolCache() { return false; }
123 public boolean isCompiledICHolder() { return false; }
124
125 // Align the object size.
126 public static long alignObjectSize(long size) {
127 return VM.getVM().alignUp(size, VM.getVM().getMinObjAlignmentInBytes());
128 }
129
130 // All vm's align longs, so pad out certain offsets.
131 public static long alignObjectOffset(long offset) {
132 return VM.getVM().alignUp(offset, VM.getVM().getBytesPerLong());
133 }
134
135 public boolean equals(Object obj) {
136 if (obj != null && (obj instanceof Oop)) {
137 return getHandle().equals(((Oop) obj).getHandle());
138 }
139 return false;
140 }
141
142 public int hashCode() { return getHandle().hashCode(); }
143
144 /** Identity hash in the target VM */
145 public long identityHash() {
146 Mark mark = getMark();
147 if (mark.isUnlocked() && (!mark.hasNoHash())) {
148 return (int) mark.hash();
149 } else if (mark.isMarked()) {
150 return (int) mark.hash();
151 } else {
152 return slowIdentityHash();
153 }
154 }
155
156 public long slowIdentityHash() {
157 return VM.getVM().getObjectSynchronizer().identityHashValueFor(this);
158 }
159
160 public void iterate(OopVisitor visitor, boolean doVMFields) {
161 visitor.setObj(this);
162 visitor.prologue();
163 iterateFields(visitor, doVMFields);
164 visitor.epilogue();
165 }
166
167 void iterateFields(OopVisitor visitor, boolean doVMFields) {
168 if (doVMFields) {
169 visitor.doCInt(mark, true);
170 if (VM.getVM().isCompressedOopsEnabled()) {
171 visitor.doOop(compressedKlass, true);
172 } else {
173 visitor.doOop(klass, true);
174 }
175 }
176 }
177
178 public void print() { printOn(System.out); }
179 public void printValue() { printValueOn(System.out); }
180 public void printRaw() { printRawOn(System.out); }
181
182 public static void printOopValueOn(Oop obj, PrintStream tty) {
183 if (obj == null) {
184 tty.print("null");
185 } else {
186 obj.printValueOn(tty);
187 tty.print(" @ " + obj.getHandle());
188 }
189 }
190
191 public static void printOopAddressOn(Oop obj, PrintStream tty) {
192 if (obj == null) {
193 tty.print("null");
194 } else {
195 tty.print(obj.getHandle().toString());
196 }
197 }
198
199 public void printOn(PrintStream tty) {
200 OopPrinter printer = new OopPrinter(tty);
201 iterate(printer, true);
202 }
203
204 public void printValueOn(PrintStream tty) {
205 try {
206 tty.print("Oop for " + getKlass().getName().asString());
207 } catch (java.lang.NullPointerException e) {
208 tty.print("Oop");
209 }
210 }
211
212 public void printRawOn(PrintStream tty) {
213 tty.print("Dumping raw memory for ");
214 printValueOn(tty);
215 tty.println();
216 long size = getObjectSize() * 4;
217 for (long i = 0; i < size; i += 4) {
218 long memVal = getHandle().getCIntegerAt(i, 4, true);
219 tty.println(Long.toHexString(memVal));
220 }
221 }
222
223 public boolean verify() { return true;}
224
225 // Package-private routine to speed up ObjectHeap.newOop
226 static OopHandle getKlassForOopHandle(OopHandle handle) {
227 if (handle == null) {
228 return null;
229 }
230 if (VM.getVM().isCompressedOopsEnabled()) {
231 return handle.getCompOopHandleAt(compressedKlass.getOffset());
232 } else {
233 return handle.getOopHandleAt(klass.getOffset());
234 }
235 }
236 };